It feels like this deck will usually stall out from a lack of spells to cast, rather than a lack of mana. The first spells I would include to help this would be Visions of Beyond, Abundant Harvest, Chart a Course, Frantic Search, and maybe Gitaxian Probe and Memory Jar.
Wheel of Fate is a decent option for additional card draw, however, I often found myself not wanting to cast it off of a cascade, because I really liked or needed cards in hand, or I actually had like 20 something cards and just needed some mana. It is also the worst of the suspend cards to actually suspend, as it gives your opponents the heads up to empty their hands, and you many not want to cast it once you finally can anyways... I've found that Windfall substitutes nicely for the other wheels.
Wheel of Fortune and Timetwister are not included in this list, mostly because they are expensive and hard to get for most people, including myself. Likewise with Lion's Eye Diamond. Furthermore, Laboratory Maniac and Thassa's Oracle style win conditions are not included as they are ultimately dead cards outside of the one circumstance, and although the deck can draw it's self out, it is designed to win via storm. If this package were included, I would probably put in Notion Thief too...
There are no counterspells included in this list, which may seem unusual for a blue storm deck, especially since it is so vital to ensure that Yidris can connect. However, they are completely useless off of cascade. The lack of counterspells is another reason I didn't include the wheels package, as the self-mill win is risky if not protected by countermagic. Veil of Summer and Autumn's Veil seem like some of the better "counterspells" to include, but the one counterspell I do really like in here is Unsubstantiate, as it can be used off a cascade. It can remove a pesky creature so that Yidris can get through. It can bounce your own creature to recast for more cascade and storm, or otherwise save them from something worse. It can even be used to bounce a spell with storm from the stack back to your hand, resulting in the storm copies still resolving, and the original copy of the card back in your hand to cast again!
For similar reasons as the tutors, Sensei's Divining Top is not included either. I do like the card:Bola's Citadel and Helm of Awakening combo with the top, and the Helm and Citadel are already included, but the Top on it's own is not quite strong enough, and is often awkward with cascade. (See my deck:11-04-21-elsha-of-the-infinite-storm deck for more on this combo, except with Future Sight, and Elsha of course...)
Isochron Scepter is not included, even though Dramatic Reversal is, and there are several other decent candidates, this combo is a little to conditional for me, including the Scepter feels like including Future Sight to me, just not quite impactful enough on it's own to justify a slightly off track, albeit powerful, combo.
Similarly to other powerful packages not included in this deck, Doomsday. It's just not quite that kind of deck. See my new deck:tasigur-creatureless-oathdoomsday deck for some Doomsday Isochron Scepter action, still in testing phase.
card:Sylan Library, too slow? Pointless during a cascade chain when you're trying to win that turn...
Mystic Remora, who cares? Again, like Sylvan Library, this doesn't help during a cascade chain, and smart people will just not feed it, and it will just be a weak like stall piece? When everyone has learned not to feed the fish, no one will play with this card anymore, unless they are going up against a storm player...!
